Teichmann Defense

The Teichmann Defense meets the accepted Blackmar-Diemer Gambit with 5...Bg4. The pin on the f3-knight sets up its exchange, which removes a key defender of d4 and e5 and reduces White's central control. The standard reply is 6. h3, by far the most played, though 6. Bc4 and 6. Bd3 also occur. After 6. h3 Bxf3 7. Qxf3 c6, Black keeps the queenside knight home for now, since 7...Nc6 runs into 8. Bb5. White must then decide how to handle the attack on d4. The Ciesielski Variation, 8. Qf2, protects the pawn but lets Black prepare ...e5 comfortably, for example 8...Nbd7 9. Bd3 e5. The Classical Variation, 8. Be3, guards d4 with a piece and aims for a gradual kingside buildup. The Seidel-Hall Attack, 8. g4, gives up the d-pawn for kingside play, as in 8...Qxd4 9. Be3 Qe5 10. O-O-O e6 11. g5. Black may also decline the bishop trade with 6...Bh5 7. g4 Bg6 8. Ne5, which often transposes to the Gunderam Defense. The engine considers the position roughly balanced, but White scores well in online play.